From Aerospace to Architecture

3D Reverse Engineering in the Renovation of Boston's Historic Little Building

Imagine dangling from a 12-story building in freezing temperatures, faced with the task of scanning every inch of the structure's decorative façade with a handheld device in your gloveless hand.

Engineers from the Quebec-based company Creaform did just this back in January 2014. Their mission was to manually record every detail of the exterior of the historic Little Building in downtown Boston so that it can be "reverse-engineered" in a studio. Hanging from ropes used for high-rise window washing, they scaled this neo-Gothic building on Bolyston Street, which was built by Clarence Blackall in 1917, braving the wind and cold.

Producing a digital image of the building's shell is just one small step in the much bigger project of renovating of the Little Building in Boston, which is owned by Emerson College and used as a student dormitory. The Boston Redevelopment Authority approved plans for the $100,000,000 expansion and renovation of the building on April 22, 2015. Elkus Manfredi Architects is in charge of the project, and Existing Conditions Surveys (ECS), founded by Kurt Yeghian, has been handling the complex process of restoring the façade.

These handheld scanners were originally designed for the aeronautics industry. NASA purchased their HandySCAN model in 2007 and uses it to inspect and reverse engineer parts of a space shuttle, even while deployed in outer space. While still in flight, astronauts can use such scanners to assess damage, running them over cracks and other weaknesses in a shuttle's exterior. Images are then sent back to engineers on the ground. Aside from being portable, these scanners are self-positioning and thus can be used in "nonlinear environments."

Its use in the renovation of the Little Building marks the introduction of this technique into architecture. While at first glance historic preservation would appear to give preference to old techniques over new ones, the use of this tool on the Little Building demonstrates that technological innovation is part-and-parcel of the process of historic preservation.

Main image: Restoring the facade of the Emerson Little Building. Image courtesy of Kurt Yeghian.